In a radio communication system that performs transmission and reception using a microwave or a millimeter wave band, a band-pass filter is used to make only a signal of a desired frequency band pass, and to remove a signal of an unnecessary bandwidth. When a band-pass filter is used at a plurality of center frequencies, there is a technological case described in patent literature 1. In patent literature 1, there is disclosed a technology in which, in the metal housing of a semi-coaxial band-pass filter, a dielectric having a movable structure is provided and a resonance frequency of a resonator is made to be changed by moving this.